A combustion chamber assembly unit for a vaporizing burner, in which a pot-like or shell-like bottom part is designed with a bottom wall and with a circumferential wall extending in the direction of a combustion chamber from the bottom wall, is known from DE 10 2005 032 980 A1. A disk-like porous evaporator medium is provided in this shell-like structure of the bottom part. A housing part surrounding the bottom part radially on the outside has, to axially support the bottom part, a radially inwardly extending, flange-like contact area, which extends over the circumferential wall of the bottom part, on the one hand, and over the radially outer area of the porous evaporator medium, on the other hand. An intermediate contact element having a ring-shaped design and made of porous material is located between this flange-like contact area and the radially outer area of the porous evaporator medium. This intermediate contact element, also called wick ring, ensures that fuel is prevented from being discharged in the liquid form or in the form of droplets in the radially outer area of the porous evaporator medium during a start phase, when the rate of evaporation of the fuel from the porous evaporator medium is comparatively low because of comparatively low temperatures of the components.
The bottom part held together with the housing part surrounding this in the axial direction is ensured by a circlip, which is locked onto the housing part and presses the bottom part against the flange-like contact area via the intermediary of the intermediate contact element or wick ring. Since further assembly units, especially an electrically energizable heating arrangement, are also located between this circlip and the bottom part, there is basically a risk that the bottom part is pressed too strongly against the intermediate contact element because of the existing manufacturing tolerances and this intermediate contact element is pressed correspondingly strongly against the flange-like contact area, so that the pore structure of the intermediate contact element is compressed so greatly that it cannot sufficiently assume its function any longer. Since the contact pressure between the intermediate contact element and the flange-like contact area may, in principle, only be limited, the porous evaporator medium also cannot, furthermore, be pressed sufficiently strongly against the bottom part in the radially outer area of the porous evaporator medium. In order to achieve a pressing contact guaranteeing a defined and good heat transfer between the porous evaporator medium and the bottom part, it is therefore necessary to bind the porous evaporator medium more strongly to the bottom part at a plurality of points by connection in substance, i.e., for example, by welding, which leads to additional expenditure of labor.